1. Field of the Invention
The present invention generally relates to a clamp used to secure hoses, boots or similar structures around a cooperating structure. More specifically, this invention relates to a low profile clamp which is particularly adapted to clamp a boot to the hub of a constant velocity joint having a restricted space within which the clamp must reside and where the lubricant contained within the boot tends to be forced outward between the boot and the hub due to the high centrifugal forces associated with a constant velocity joint.
2. Description of the Prior Art
Clamping devices such as clamping bands are well known in the art and are extensively used to secure hoses, boots and the like to cylindrically-shaped members. Clamping bands generally include a body portion having oppositely disposed ends which may or may not overlap each other, and means for securing the ends or the overlapping portions of the clamping band together to retain the clamping band on the hose or boot. Typically the clamping band serves to seal the hose or boot against the cylindrical member to prevent escape of any fluid contained therein, and further to ensure that the hose or boot is securely retained on the cylindrical member.
A common problem with clamping bands is the limited space in which the device must reside. Also, for certain reasons pertaining to mechanical dynamics it may be undesirable for portions of the device to project too far outside the perimeter of the hose or boot. One approach to limiting these undesirable consequences is disclosed in U.S. Pat. No. 4,802,261 to Mizukoshi et al. There, the opposing free ends and of the band body overlap each other. Within the region of the overlapping free end there is provided an aperture having a projection extending radially downward toward the overlapped free end. On the overlapped free end is a series of radially upwardly extending projections for cooperating with the projection to retain the band body in a clamping position around a body to be clamped. A pair of bent portions is welded to the underside of the overlapped free end. The bent portions act to maintain engagement between the projection and one of the series of projections. The overall thickness of the band body is, therefore, at a maximum at the bent portions. The combined thicknesses of the overlapping and overlapped free ends plus the thickness of the bent portions passing below the overlapped free end and passing above the overlapping free end result in a total of four thicknesses.
A shortcoming of the clamping band disclosed by Mizukoshi et al is the radial gap created at the point where the free ends begin to overlap each other. The gap tends to extend along a significant portion of the circumference of the clamp, reducing the clamping effect of the band body 10 on the clamped body 54 in that region. Thus, a path is provided that will allow leakage of fluid contained within the hose or boot if the fluid is under high pressure or if it experiences localized pooling due to internal or external dynamic forces.
To avoid this shortcoming, U.S. Pat. No. 4,237,584 to Oetiker expressly teaches away from the use of overlapping ends in the design of a clamping band. There, the opposing ends of the clamping band are formed to fit together in a tongue-and-fork fashion. The method of maintaining a clamping action is accomplished by providing a clamping member to the clamping band. The clamping member has a series of teeth which engage a series of cut-out portions that are disposed adjacent each end of the clamping band. What is commonly referred to as an "Oetiker ear" is centrally disposed on the clamping member between sets of teeth. To draw the clamping band tight around the member to be clamped, the ear is contracted to draw the series of teeth toward the ear, pulling the ends of the clamping band together.
A primary disadvantage to the Oetiker clamping band is the projection of the ear above the perimeter of the clamping band. In applications where space is at a premium or where adverse effects may result from a non-symmetrical construction, the ear presents a major shortcoming.
From the above discussion, it can be readily appreciated that the prior art does not teach a clamping band which simultaneously minimizes the gap created by the overlapping ends of the band while providing a low profile.
Therefore, it would be desirable to provide a clamping band with the advantages of a clamping band having overlapping ends because of its ability to provide a low profile. It would be additionally desirable to provide a clamping band which simultaneously minimizes any gap created by the overlapping ends. As taught by Oetiker, it is not economically feasible to minimize the gap created by overlapping ends by grinding the overlapped end to be thinner because of the added costs of the grinding step and the undesirable compromises required in selecting a band material that can be readily ground.
Accordingly, what is needed is a clamping band which employs overlapping ends thereby facilitating a low profile of the clamping band, while also providing unique features that minimize the gap created by the overlap.